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基于C++的读者与写者问题read—write problem的实现(6)

2013-07-08 01:38 ;  //延迟时间
 DWORD m_persist;                   //读文件持续时间
 int m_serial;                      //线程的序号
 //从参数中得到信息
 m_serial=((ThreadInfo*)(p))->serial ;

 m_delay=(DWORD)(((ThreadInfo*)(p))->delay *INTE_PER_SEC);
 m_persist=(DWORD)(((ThreadInfo*)(p))->persist *INTE_PER_SEC);
 Sleep(m_delay);                  //延迟等待

 printf("Reader thread %d sents the reading require.\n",m_serial);
 wait_for_mutex1=WaitForSingleObject(h_Mutex1,-1);

 //读者进去临界区
 EnterCriticalSection(&cs_Read);

 //阻塞互斥对象Mutex2,保证对readCount的访问和修改互斥
  wait_for_mutex2=WaitForSingleObject(h_Mutex2,-1);
  //修改读者的数目
  readcount++;
  if(readcount==1)
  {
   // 如果是第1个读者,等待写者写完
   EnterCriticalSection(&cs_Write);
  }
  ReleaseMutex(h_Mutex2);// 释放互斥信号 Mutex2
  //让其他读者进去临界区
  LeaveCriticalSection(&cs_Read);
  ReleaseMutex(h_Mutex1);
  //读文件
  printf("Reader thread %d begins to read file.\n",m_serial);
  Sleep(m_persist);

  //退出线程
   printf("Reader thread %d finished reading  file.\n",m_serial);
   //阻塞互斥对象Mutex2,保证对readcount的访问,修改互斥
   wait_for_mutex2=WaitForSingleObject(h_Mutex2,-1);
   readcount--;
   if(readcount==0)

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   {
    //最后一个读者,唤醒写者
    LeaveCriticalSection(&cs_Write);
   }
   ReleaseMutex(h_Mutex2);  //释放互斥信号
}
///////////////////////////////////////////
//写者优先---写者线程
//P:写者线程信息

void WP_WriterThread(void *p)
{
 DWORD wait_for_mutex3;            //互斥变量
 DWORD m_delay;                   //延迟时间
 DWORD m_persist;                 //读文件持续时间
 int m_serial;                    //线程序号

 HANDLE h_Mutex3;
 h_Mutex3=OpenMutex(MUTEX_ALL_ACCESS,FALSE,"mutex3");

 //从参数中获得信息
 m_serial=((ThreadInfo*)(p))->serial ;
 m_delay=(DWORD)(((ThreadInfo*)(p))->delay *INTE_PER_SEC);
 m_persist=(DWORD)(((ThreadInfo*)(p))->persist *INTE_PER_SEC);
 Sleep(m_delay);                  //延迟等待

 printf("Writer thread %d sents the reading require.\n",m_serial);
 wait_for_mutex3=WaitForSingleObject(h_Mutex3,-1);
 writecount++;            &nb